From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8951C76195 for ; Tue, 28 Mar 2023 06:17:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232702AbjC1GRv (ORCPT ); Tue, 28 Mar 2023 02:17:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232578AbjC1GRX (ORCPT ); Tue, 28 Mar 2023 02:17:23 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 259513A88 for ; Mon, 27 Mar 2023 23:16:55 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id b16-20020a17090a991000b0023f803081beso2939413pjp.3 for ; Mon, 27 Mar 2023 23:16:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1679984214; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=0xrFtgulASYXrMO3GaE6CpeYp9Puj0hiviKaUT94oIg=; b=qIxeFfAv7LZhUaMY9U0TvTtrAPX4wRqNbnIeY0Yrn/RnFRGntBTlu0hfuIAsMfAy2n 1P28EpdkOB3njh6q599A6aRPcbQ+/6Ngp2xMzs6rBLHlr6vd8s4xgEvIn8RMUD6Mze8g o6DwJQ//Mohpbdf8YD2EiOxbMyBh8HdrF+/Yzlad7E0D+Fg0j+P6NKtF5T845D/HLRrp rP0WF5ztka030C2opL/oGdjy+y9vRWrHiXRiQXH/e0QgpKRtMDaGNueTHyNdIDcH2xFM Q3P8IwnLdzShQrK/qG/mnGtQghgE6XGNQRvgt1djyelN/qv5GiJdyRld4l0gXlsYj6Rl orEw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679984214; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0xrFtgulASYXrMO3GaE6CpeYp9Puj0hiviKaUT94oIg=; b=qQhF9DdaOiY3TQjhmFuPZBQ3i2vs1MVqzTemCNyQcqUHeaQb/+z3Tsi7ij7TSe6fGa mxGc+/JGDuFdrEjzvVma3UUhHR3YDsMmZrBKtCI5HgQ5866ly6ZwY4D+q044GFZoVYW6 iCgjFmiqJuVnxjq3UEQwOdpcDzrr/nTHgxpD84jg8fveKfn34TS8RKbpd4t/Tyw+BzRf PgNGFa3nDLgin2O5ENmlu1PlHG0S4wJ9AXzCB5hHlAV+n+bNRT1fQ80QkpllL3739d1k gCipq1eRTP7AO93nL5UXR+JGhRFDYMN7+bXpXE2UTHjIFf6jl8iHfYIb06X8HaaAiFuT tAeQ== X-Gm-Message-State: AAQBX9c7v+ZJ25GjU6L2EwzCQFd+beJE4ddoE4tyM0ETtMd/WA6vMSZe bbjKAh/SN97gH3P9Ecr9HbdLdpIuxbUUBf0v X-Google-Smtp-Source: AKy350aBuKbfjhOAuCJYm2iwk4HKu8S/jfcCuw8uP63TY3FEEFp0rTq/+r6BOwoVOwDyCp4xkVINZeVu5jFTXH9F X-Received: from yosry.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:2327]) (user=yosryahmed job=sendgmr) by 2002:a63:115a:0:b0:50b:dfd4:b56f with SMTP id 26-20020a63115a000000b0050bdfd4b56fmr3747909pgr.5.1679984214584; Mon, 27 Mar 2023 23:16:54 -0700 (PDT) Date: Tue, 28 Mar 2023 06:16:36 +0000 In-Reply-To: <20230328061638.203420-1-yosryahmed@google.com> Mime-Version: 1.0 References: <20230328061638.203420-1-yosryahmed@google.com> X-Mailer: git-send-email 2.40.0.348.gf938b09366-goog Message-ID: <20230328061638.203420-8-yosryahmed@google.com> Subject: [PATCH v1 7/9] workingset: memcg: sleep when flushing stats in workingset_refault() From: Yosry Ahmed To: Tejun Heo , Josef Bacik , Jens Axboe , Zefan Li , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , "=?UTF-8?q?Michal=20Koutn=C3=BD?=" Cc: Vasily Averin , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, Yosry Ahmed Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In workingset_refault(), we call mem_cgroup_flush_stats_ratelimited() to flush stats within an RCU read section and with sleeping disallowed. Move the call to mem_cgroup_flush_stats_ratelimited() above the RCU read section and allow sleeping to avoid unnecessarily performing a lot of work without sleeping. Since workingset_refault() is the only caller of mem_cgroup_flush_stats_ratelimited(), just make it call the non-atomic mem_cgroup_flush_stats(). Signed-off-by: Yosry Ahmed --- mm/memcontrol.c | 12 ++++++------ mm/workingset.c | 4 ++-- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 57e8cbf701f3..0c0e74188e90 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -674,12 +674,6 @@ void mem_cgroup_flush_stats_atomic(void) __mem_cgroup_flush_stats_atomic(); } -void mem_cgroup_flush_stats_ratelimited(void) -{ - if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) - mem_cgroup_flush_stats_atomic(); -} - /* non-atomic functions, only safe from sleepable contexts */ static void __mem_cgroup_flush_stats(void) { @@ -695,6 +689,12 @@ void mem_cgroup_flush_stats(void) __mem_cgroup_flush_stats(); } +void mem_cgroup_flush_stats_ratelimited(void) +{ + if (time_after64(jiffies_64, READ_ONCE(flush_next_time))) + mem_cgroup_flush_stats(); +} + static void flush_memcg_stats_dwork(struct work_struct *w) { __mem_cgroup_flush_stats(); diff --git a/mm/workingset.c b/mm/workingset.c index af862c6738c3..7d7ecc46521c 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -406,6 +406,8 @@ void workingset_refault(struct folio *folio, void *shadow) unpack_shadow(shadow, &memcgid, &pgdat, &eviction, &workingset); eviction <<= bucket_order; + /* Flush stats (and potentially sleep) before holding RCU read lock */ + mem_cgroup_flush_stats_ratelimited(); rcu_read_lock(); /* * Look up the memcg associated with the stored ID. It might @@ -461,8 +463,6 @@ void workingset_refault(struct folio *folio, void *shadow) lruvec = mem_cgroup_lruvec(memcg, pgdat); mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr); - - mem_cgroup_flush_stats_ratelimited(); /* * Compare the distance to the existing workingset size. We * don't activate pages that couldn't stay resident even if -- 2.40.0.348.gf938b09366-goog